But this is not officially supported so take care. You could damage your device.

v1.1 was released less than two weeks ago so ZTE may have a bit more work to do. Hopefully it won't be too much longer.

Hello,
The device manufacturers are the ones that push out Firefox OS updates. My understanding is that ZTE are working on the 1.1 update at the moment and hopefully will push it out to devices soon.
It may be possible to flash the 1.1 update onto your device manually if you root the device. See the discussion thread below:
https://groups.google.com/forum/#!topic/mozilla.dev.b2g/q20PteboREo
But this is not officially supported so take care. You could damage your device.
v1.1 was released less than two weeks ago so ZTE may have a bit more work to do. Hopefully it won't be too much longer.